[10] MacArthur faced Democratic nominee Aimee Belgard, a Burlington County freeholder, in the general election.

[11][12] MacArthur outspent Belgard by about three to one (with both campaigns' spending equaling a combined total of $7.4 million), making the race the most expensive open-seat contest in the country in 2014.

[18] On March 25, 2015, MacArthur introduced the "Veterans' Mental Health Care Access Act"[19] to allow veterans with a Choice Card to access mental health care at any facility eligible for reimbursement by the Centers for Medicare and Medicaid Services.

[20][21] Both bills were considered "dead," by virtue of a failure to garner approval from Republican-led subcommittees, before the final sine die Adjournment of the 114th Congress.

[34] MacArthur was defeated by Democrat Andy Kim, a former national security aide to President Obama, in the midterm election on November 6.

[39][40][41][42] Kim highlighted MacArthur's prominent role in the Republican efforts to repeal and replace the Affordable Care Act, while emphasizing his own experience in national security and his refusal to accept corporate PAC donations.

[48][49][50] Committee assignments 115th Congress 114th Congress Caucus and leadership positions MacArthur was elected or assigned to several leadership roles during his tenure, including Co-Chair of the Tuesday Group (a group of moderate or centrist Republicans), Co-Chair of the Bipartisan Heroin and Opioid Taskforce,[51] and Commissioner of the Puerto Rico Growth Commission.

[52] MacArthur also was a member of the Board of Directors of the National Republican Campaign Committee, and Trustee of the Kennedy Center of the Performing Arts.

"[60] MacArthur was the only member of the New Jersey congressional delegation to vote in favor of a bill that funded farm subsidies for five additional years while imposing work requirements and new restrictions on food stamp usage.

[65] According to Vote Smart's 2016 analysis, MacArthur generally opposes allowing individuals to divert a portion of their Social Security taxes into personal retirement accounts.

[69] MacArthur opposes the Trump administration's proposal to open New Jersey's waters to offshore oil and gas drilling.

[66] MacArthur had described himself as a supporter of the Second Amendment and was endorsed by the NRA Political Victory Fund with a 93% ("AQ") rating.

[71][72][73][74] MacArthur became a key player in efforts to repeal and replace the Affordable Care Act, citing the loss of his first child and his own background in insurance as motivating factors.

It also dictates that health insurance offered to members of Congress and their staffs not be included in the exemption from covering pre-existing conditions.

[83] A Washington Post-ABC News poll conducted in April 2017, found that 70 per cent of Americans favored protections for pre-existing conditions.

[6][100] In Gracie's memory, the MacArthurs founded In God's Hands Charitable Foundation, which funds programs that help wounded veterans and children affected by AIDS in Africa.

[101] During his time in office, MacArthur was the wealthiest member of New Jersey's congressional delegation, with minimum reported assets worth about $31.8 million as of July 2017.

[104] MacArthur owns and operates multiple businesses in the marina and hospitality sectors, including the Bayview Harbor marina[105][106] and the affiliated Sandcastle Luxury Bed and Breakfast,[107] both in Barnegat Light, NJ, and a yacht holding company which operates a vacation rental and charter yacht.